Prince Ceidio of Gwent became
embroiled in political intrigue while still a baby, for he escaped with
his mother, Queen (& Saint) Madrun of Gwent, from the flames of
High-King Vortigern's last stand at Tre'r Ceiri. He settled at Llangeidio
just north of his mother's hillfort on Carn Fadrun, and founded a church
there. Like many Celtic saints, upon taking up the religious life, he may
have become associated with a sanctuary-seeking deer, for his horse
was called one of the three "cloven-hoofed horses" of Britain.
He founded other churches in Wales at Ceidio (Llandyrnog) and Rhaeadr (Gwerthrinion),
but later took his mother to Cerniw to evangelize the people of Minster.
He is sometimes, mistakenly, recorded as Cynheiddon and should not be
confused with St. Ceidio ap Caw.